Cutting out after 30 minutes

[pwcskier]

I am working on a 96 WVenture 1100 that starts cutting out after 30 minutes. We have replaced voltage regulator, spark plugs, ignition coils, pickup coils, fuel filter, cleaned carbs, checked fuel lines, petcock, compression, and check valve.
The ski runs great up to the 30 minutes mark. It then starts having a slight miss that progressively becomes worses.

Any suggestions would be appreciated.
Dave

[Technical Support]

do you notice the engine getting fairly hot when this happens?

[VINCE_g]

Take a timimg light out w/you and see if its ignition related.

[torquenut]

Hate to sound ignorant but how is the light thing done? just mark the PTO with some chalk and mark what ever for the timing mark? Never heard of this done on a jet ski, done on outboards, and cars but not on ski'?

[ September 19, 2003, 11:33 PM: Message edited by: torquenut ]

[Marky]

What kind of compression do you have on each cylinder?

[Marky]

These boats are notorious for having the over heat sensor going bad,even intermittantly.They exhibit the same symptom,cutting out on one or two cylinders.replace the overheat sensor in the head and check the cooling system for any blockage.You could also have a partially block cooling passage or outlet or cooling hose that causes the ski to overheat after running for a little while.I think the culprit is most likely the overheat sensor,when I worked at the dealership they often had failures.

Good Luck

[superjtrdr]

Sounds like the heat sensor but have you tried switching the fuel to reserve or bypassing it. My superjet had the same problem. After weeks of troubleshooting I switched the fuel to on and the problem went by by. Keeping it on reserve is the way I normally ride.

[pwcskier]

Sorry for taking so long getting back onto the forum. It took 3 emails and 2 phone calls before I could get someone to reset my password.

It is not fuel related as I have rebuilt the carbs, blew out the fuel lines, cleaned the petcock. Not heat sensor related as I have bypassed (unplugged) the sensor. Not overheating. Compression is 151/150/150. Crank is not twisted.

I have not used a timing light as the ski runs great for 30 minutes so timing is not an issue.

Dave